Calico Life Sciences said the FDA has granted Breakthrough Therapy Designation to fosigotifator for the treatment of Vanishing White Matter (VWM) disease, an ultra-rare, progressive leukoencephalopathy with no approved therapies. Fosigotifator is an investigational eIF2B activator now being studied in a Phase 1b/2 clinical trial assessing safety, tolerability, pharmacokinetics and exploratory efficacy in adult, pediatric and infant patients with VWM disease.
Breakthrough Therapy Designation is reserved for investigational drugs intended to treat serious or life-threatening conditions when early clinical evidence suggests they may offer substantial improvement over existing therapies on one or more clinically meaningful endpoints. The designation for fosigotifator follows its earlier selection for the FDA’s Support for clinical Trials Advancing Rare disease Therapeutics (START) program, which is aimed at accelerating development of treatments for rare diseases. Calico said preliminary clinical findings, together with the new regulatory status, support continued development of the candidate in VWM.
VWM is caused by variants in any of the five subunits of the essential cellular enzyme eIF2B, leading to reduced enzymatic activity and chronic activation of the integrated stress response (ISR), a pathway involved in protein homeostasis and organismal resilience. In the central nervous system, persistent ISR activation drives degeneration of white matter, resulting in symptoms such as impaired movement, cognitive decline and seizures, along with shortened life expectancy. Although symptoms most often emerge between ages 2 and 6, the disease can present at any age, and stressors such as fever, infections or mild head trauma may trigger episodes of rapid clinical deterioration. There is currently no cure and no approved treatment for VWM disease.
Subscribe to our e-Newsletters
Stay up to date with the latest news, articles, and events. Plus, get special offers
from American Pharmaceutical Review – all delivered right to your inbox!
Sign up now!